1. Field of the Invention
The present invention relates to a solid-state image pickup apparatus and an electronic apparatus. In particular, the present invention relates to a solid-state image pickup apparatus having a waveguide structure and an electronic apparatus including the solid-state image pickup apparatus.
2. Description of the Related Art
As a solid-state image pickup apparatus, a so-called surface-incident-type solid-state image pickup apparatus is generally used. The solid-state image pickup apparatus of the surface incident type takes incident light from a surface (front surface) on a wiring layer side of an element formation portion on which a photoelectric converter is formed. The solid-state image pickup apparatus of the surface incident type has a structure in which pixel components such as a wiring layer, a protection film, a color filter, and a micro lens are provided on an area of a photoelectric converter.
Incidentally, in a solid-state image pickup apparatus such as a solid-state image pickup apparatus of the surface incident type, miniaturization of a pixel size (cell size) up to approximately 1 μm inevitably causes a reduction in light amount of image light (incident light) that is focused on a micro lens. In addition, because a wiring layer and the like are intervened between a micro lens and a photoelectric converter, a loss of the light amount is significantly generated in the wiring layer and the like, until light focused on a micro lens reaches a photoelectric converter. As a result, a sensitivity of a pixel is significantly deteriorated.
In view of this, to efficiently guide light to a photoelectric converter, that is, to increase light collection efficiency, there have been proposed various solid-state image pickup apparatuses having a so-called waveguide structure in which a waveguide is provided in a center portion of a pixel, and light is confined in the waveguide, thereby suppressing the loss of the light amount (see, for example, Japanese Patent Application Laid-open No. 2008-210975).